Sensitivity and Specificity of the Alvarado Score for the Timely Differential Diagnosis of Acute Appendicitis in Samoa

Retrospective clinical data review design of all patients admitted to the Tupua Tamasese Meaole Hospital Surgical Unit for AA from January 2015 to December 2016. Exclusion criteria were appendiceal abscess and/or mass, and final diagnosis 'not acute appendicitis'. Age, sex, village, Alvarado Score, Ultrasound Scan Result, surgical management, and histopathology result were the main variables entered into the SPSS statistical software package for analysis.

Study Overview

• Status: Completed
• Conditions: Acute Appendicitis
• Intervention / Treatment: Other: Alvarado Score

Detailed Description

METHODS

Study Design and Data Collection

A retrospective study design was used to evaluate all AA cases seen by the Surgical Department of TTM Hospital over the 24-month period between 1 January 2015 and 31 December 2016. The clinical medical records were obtained from the National Health Service PATIS System, using the search terms 'appendicitis', 'acute appendicitis', and 'appendicectomy'. A total of 289 records were retrieved. Thirty four (34) records were excluded having met the exclusion criteria: (1) final diagnosis was not AA (i.e., ectopic pregnancy, tubal ovarian abscess, other gynaecological pathologies, diverticulitis, Merkel diverticulitis, perforated ulcer), and (2) appendiceal abscess and/or appendiceal mass. Thirty (30) clinical records with missing data, and these were also excluded from the study. The final number of included for analysis was 225 cases. All 225 cases were initially treated with intravenous antibiotics upon presentation to the emergency department as per the National Health Service antibiotic guidelines: intravenous ceftriaxone and metronidazole was the first line of treatment, and alternative antibiotics were administered if unavailable (i.e., clindamycin + gentamycin or ampicillin, or gentamycin + metronidazole).

A purpose-designed data collection form and excel spreadsheet were created for the study. The following information was extracted from the clinical records: patient gender (male/female), age (years), address (urban/rural), time of admission (Morning/Afternoon/Night Shift), use of traditional/alternative medicine prior to attending emergency department (yes/no), administration of antibiotics by emergency department staff (yes/no), Alvarado Score (1-10), Ultrasound Scan for AA (Positive/negative/Inconclusive/Not performed), management of AA (appendicectomy/antibiotic therapy), intra-operative macroscopic examination (Grade 1-5), histopathology result for AA (Positive/Negative/Inconclusive/Not available), length of stay in hospital (days), and mortality (yes/no).

Data analysis The data was analysed using the SPSS (Version 2.1) statistical software package. Descriptive analysis was performed, and the chi-square test of significance was used to investigate for statistically significant differences between variables (significant at p<0.05). The sensitivity, specificity, Positive Predictive Value (PPV), and Negative Predictive Value (NPV) were calculated for the Alvarado Score in identifying AA as confirmed by histopathology.

• Study Type: Observational
• Enrollment (Actual): 225

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

All Acute Appendicitis cases seen by the Surgical Department of TTM Hospital over the 24-month period between 1 January 2015 and 31 December 2016.

The final number of included for analysis was 225 cases.

Description

Inclusion Criteria:

• All Acute Appendicitis (AA) cases seen by the Surgical Department of TTM Hospital over the 24-month period between 1 January 2015 and 31 December 2016.

Exclusion Criteria:

• Final diagnosis was not Acute Appendicitis (i.e., ectopic pregnancy, tubal ovarian abscess, other gynaecological pathologies, diverticulitis, Merkel diverticulitis, perforated ulcer)
• Final diagnosis was appendiceal abscess and/or appendiceal mass.
• Clinical records with missing data

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Other

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Effectiveness of the Alvarado Score for the identification of acute appendicitis in Samoa	The sensitivity of the Alvarado Score will be calculated for correct diagnosis of acute appendicitis based on confirmed acute appendicitis by histopathology results	24 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Accuracy of the Alvarado Score for the identification of acute appendicitis in Samoa	The specificity of the Alvarado Score will be calculated for correct diagnosis of acute appendicitis based on confirmed cases of acute appendicitis by histopathology	24 months

Collaborators and Investigators

• Sponsor: Dr Annette Kaspar
• Collaborators: Fiji National University

Study record dates

Study Major Dates

• Study Start (Actual): January 1, 2015
• Primary Completion (Actual): December 1, 2016
• Study Completion (Actual): December 1, 2016

Study Registration Dates

• First Submitted: November 14, 2021
• First Submitted That Met QC Criteria: December 7, 2021
• First Posted (Actual): December 23, 2021

Study Record Updates

• Last Update Posted (Actual): December 23, 2021
• Last Update Submitted That Met QC Criteria: December 7, 2021
• Last Verified: December 1, 2021

More Information

Terms related to this study

• Keywords: Alvarado Score
• Additional Relevant MeSH Terms: Digestive System Diseases; Pathologic Processes; Infections; Disease Attributes; Gastrointestinal Diseases; Gastroenteritis; Intestinal Diseases; Cecal Diseases; Intraabdominal Infections; Acute Disease; Appendicitis
• Other Study ID Numbers: s994956

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No
• IPD Plan Description: There is no plan to share IPD with other researchers.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No